1. Field of the Invention
The present invention relates to a method for manufacturing a photoelectric conversion device.
2. Description of the Related Art
Regarding a photoelectric conversion device, there is a known technique for reducing contact resistance between source-drain regions and a gate electrode of a MOS transistor, by providing these regions with a metal-semiconductor compound layer (silicide layer) containing a compound of a high melting point metal and a semiconductor. If a silicide layer is formed on a photoelectric conversion portion, a current leakage at the photoelectric conversion portion increases, and the photoelectric conversion characteristics deteriorate. Thus, in Japanese Patent Laid-Open No. 2009-026848, formation of a silicide layer on a photoelectric conversion portion is suppressed by covering the photoelectric conversion portion with a silicon nitride film that functions as a protection layer and then forming a silicide layer. Furthermore, in Japanese Patent Laid-Open No. 2009-026848, an upper side in a portion of the silicon nitride film covering the photoelectric conversion portion is removed by etching, thereby adjusting the film thickness of the above-described silicon nitride film that functions also as an antireflection film for the photoelectric conversion portion.